Agkistrodon piscivorus Northern Cottonmouth
Some other names for this species:
Water Moccasin
In 2014, Burbrink and Guiher split Agkistrodon conanti from Agkistrodon piscivorus, and eliminated the other previously distinguished subspecies.
Snake Road, La Rue-Pine Hills Ecological Area, Union County, IllinoisApril 23, 2008
Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus) Northern Cottonmouth (Agkistrodon piscivorus)
Snake Road in extreme southwestern Illinois is a dirt road through a particularly snake-friendly area of Shawnee National Forest. It's positioned between rocky bluffs that offer great winter hibernation nooks and woody wetlands that offer great summer habitat, and vast numbers of snakes head down to the water in the spring, and up to the bluffs in the fall. The road is closed each spring and fall to allow this migration to occur without lots of snakes being squished by traffic. The road is famous to snake lovers all over the country, at least. This was my first visit.

Many different snakes live in the area, but cottonmouths are by far the most commonly seen. I had never seen a cottonmouth in person before, so I certainly admired the quantity. They are venomous snakes, but not aggressive. They seem to greatly enjoy showing off the white insides of their mouths.

The first one we saw was right in the middle of the road, as was another later in the morning. Most of the others were in the water or near the road. The one in the pile of leaves with its mouth wide open was under a log.

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